Container lid with ring and method of manufacture

ABSTRACT

A container lid is provided having a lid insert constructed of a paper-based material and a peripheral ring constructed of a plastic material. The ring is configured to be separated from the lid insert upon disposal. The lid insert includes a peripheral rim extending outwardly from a central cover portion. The ring includes an outwardly extending flange and a skirt depending downwardly from the flange. A first undercut extends inwardly from the skirt defining a channel sized and shaped for receiving an outer edge of the lid insert&#39;s peripheral rim. The channel may alternatively be sized and shaped for also receiving an outer edge of a peripheral rim of a container base to which the lid is attached. Another embodiment includes a second undercut located beneath the first undercut and defining a second channel into which an outer edge of the rim of the container base may be received.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims priority to U.S. Provisional Patent Application Ser. No. 61/876,067, filed on Sep. 10, 2014, to Keegan Y. Yang et al. entitled “Molded Fiber Lid with Plastic Ring and Method of Manufacture,” currently pending, the entire disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Containers for food products are well known in the art. Such containers typically include a base and a lid. The lid may be attached to the base in various manners. However, such previously known container lids are not without shortcomings. For example, in recent years, continuing efforts have been made to increase the recyclability of packaging, and in particular, food packaging Previously known container lids made of multiple materials (e.g., paperboard and plastic) have not been recyclable due to containing such multiple materials and have therefore, upon disposal, been placed in waste that is directed for landfills.

Accordingly, a need exists for a lid made of multiple materials that can be separated so that the various different materials can be recycled or composted apart from one another.

SUMMARY OF THE INVENTION

One embodiment of the present invention is directed to a container lid adapted for interlocking attachment with a container base, wherein the lid comprises a lid insert constructed of a paper-based material (e.g., molded fiber, pressed paperboard, etc.) and a peripheral ring constructed of a different material (e.g., plastic). The ring is configured to be easily separable from the lid insert upon disposal of the lid. The lid insert may comprise a central cover portion and a generally flat and horizontal peripheral rim extending outwardly around at least part of the cover portion. The cover portion of the lid insert can include an upwardly projecting central section, which may be generally dome-shaped in one embodiment.

The ring circumscribes at least part of the lid insert's rim and includes a horizontal outwardly extending flange and a skirt depending downwardly from the flange. A first undercut or locking projection extends inwardly from the skirt. The first locking projection may be in the form of a single projection that extends substantially continuously around the entire interior periphery of the skirt or may be in the form of a plurality of peripherally-spaced projections having gaps therebetween. A first channel is defined between the first locking projection and a bottom surface of the ring's flange. The channel is sized and shaped to receive an outer edge of the lid insert's rim so as to releasably retain the lid insert's rim between the first locking projection and the bottom surface of the flange. In one embodiment, the channel is sized and shaped to receive both the outer edge of the lid insert's rim and an outer edge of a peripheral rim extending around the base.

In another embodiment, the ring includes first and second undercuts or locking projections extending inwardly from the skirt, wherein the second locking projection is located beneath the first locking projection. In this embodiment, a first channel is defined between the first locking projection and the bottom surface of the lower flange, and a second channel is defined between the second locking projection and the first locking projection. The first channel is sized and shaped to receive an outer edge of the lid insert rim, while the second channel is sized and shaped to receive an outer edge of the base rim. It will be appreciated that the ring may be injected molded either directly onto the lid insert or may be injected molded and then combined with the lid insert. Alternatively, the ring may be thermoformed and then combined with the lid rim.

In a further embodiment, the ring has a stepped cross section. In that embodiment, the ring may include a generally horizontal and outwardly extending upper flange, an upper skirt extending downwardly from the upper flange, a generally horizontal lower flange extending outwardly from the upper skirt, and a lower skirt extending downwardly from the lower flange. A first undercut or locking projection extends inwardly from the upper skirt and one or more second locking projections extend inwardly from the lower skirt, optionally at various heights about the lower skirt. A first channel is defined between the first locking projection and a bottom surface of the upper flange. A second channel is defined between at least one of the second locking projections and a bottom surface of the lower flange. A third channel may be defined between two or more of the second locking projections.

Another aspect of the present invention is directed to a method of manufacturing the lid. In the method, a paper-based material is formed into a lid insert having a peripheral rim. In one embodiment of the method, the ring may be injection molded directly around at least a portion of the lid insert rim. In another embodiment of the method, the ring may be injection molded separately from the lid insert and then subsequently combined with the lid insert. In a further embodiment of the method, the ring may be thermoformed separately from the lid insert and then subsequently combined with the lid insert.

Other aspects and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments and the accompanying drawing figures.

DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

In the accompanying drawing, which fowls a part of the specification and is to be read in conjunction therewith in which like reference numerals are used to indicate like or similar parts in the various views:

FIG. 1 is a side perspective view of a container assembly comprising a lid insert, a base and a ring attaching the lid insert to the base in accordance with one embodiment of the present invention;

FIG. 2 is an enlarged partial sectional side perspective view of a container assembly comprising a lid insert, a base and a ring securing the lid insert with the base, wherein the ring includes two undercuts located at different heights in accordance with a first embodiment of the present invention;

FIG. 3 is a side perspective view of a lid insert and ring in accordance with one embodiment of the present invention, wherein the ring is attached to the lid insert;

FIG. 4 is a side perspective view of a lid insert and ring in accordance with one embodiment of the present invention, wherein the ring is detached from the lid insert;

FIG. 5 is an enlarged partial sectional side perspective view of a container assembly comprising a lid insert, a base and a ring securing the lid insert with the base, wherein the ring includes a single undercut in accordance with a second embodiment of the present invention;

FIG. 6 is an enlarged partial sectional outer side perspective view of a container assembly comprising a lid insert, a base and a ring securing the lid insert with the base, wherein the ring includes a plurality of undercuts at various heights in accordance with a third embodiment of the present invention; and

FIG. 7 is an enlarged partial sectional inner side perspective view of the container assembly of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. For purposes of clarity in illustrating the characteristics of the present invention, proportional relationships of the elements have not necessarily been maintained in the drawing figures.

The following detailed description of the invention references specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention is defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled.

The present invention is directed generally to a container assembly 10 comprising a lid 12 adapted for interlocking placement over a receptacle or base 14, wherein the lid 12 includes a lid insert 16 and circumscribing ring 18. The lid 12 is adapted for being removably attached to the container base 14. As discussed in greater detail below, the ring 18 facilitates attachment of the lid 12 to the container base 14. In one embodiment, the lid insert 16 may be constructed of a recyclable or compostable material, such as molded fiber or pressed paperboard for example, and the ring 10 may be constructed of a recyclable plastic.

The ring 18 is designed to be easily and cleanly separated from the lid insert 16 by a consumer, such that the base 14, lid insert 16 and ring 18 can be all be separately recycled or composted upon disposal. In that regard, as discussed in more detail below, the ring 18 may include one or more undercuts, ribs, barbs, lugs or projections to facilitate mechanical attachment to the lid insert 16 and base 14 without the use of any adhesive bond. Each of these three components (i.e., the base 14, lid insert 16 and ring 18) will be discussed in further detail below.

Referring to the figures, FIG. 1 illustrates a side perspective view of one embodiment of the container assembly 10. As shown in FIGS. 1 and 2, the lid 12 includes a lid insert 16 having an upwardly projecting central cover portion 22 and a horizontal peripheral rim 24 extending radially and outwardly at least partially or fully around the cover portion 22. The lid insert 16 is sized and shaped to generally cover at least a portion of the base 14. The lid insert 16 may take form in a variety of shapes, including round, square, oval, rectangular or other suitable shapes. In one embodiment, the cover portion 22 of the lid insert 16 is generally dome-shaped. However, it will be appreciated that the cover portion 22 need not be dome-shaped and may take on any other suitable shape. The cover portion 22 and rim 24 of the lid insert 16 may be integrally formed of any suitable material, including but not limited to a cellulosic or fiber-containing material, a paper-based material, a plastic material, a metallic material or any other suitable material now known or hereafter developed. In one preferred embodiment, the lid insert 16 is constructed of a recyclable or compostable material, such as molded fiber or paperboard. The lid insert 16 may be produced in a process that results in a generally flat rim 24 or in a process that results in a variable, wavy or bowed rim 24.

The terms “paper” or paper-based” as used herein, are broad terms and include without limitation all types of paper products, such as paperboard, kraft paperboard, reprocessed paperboard, molded paper, cellulosic fiber, molded fiber, pulp slurry, corrugated paper, cardboard, coated paper, paper laminates and multi-ply paper. The term “pulp slurry,” as used herein, is a broad term and includes without limitation an aqueous slurry containing cellulose or cellulosic fiber derived from a plant or wood pulping process or paper recycling process. The term “pressed paperboard,” as used herein, is a broad term and includes without limitation paper that is constructed from a generally planar paperboard blank and deformed into shape under pressure. In an embodiment wherein the lid insert 16 is formed of pressed paperboard, generally radial score lines may be formed in the paperboard blank prior to the blank being formed into shape. The blank can then be formed into shape by a forming press that includes upper and lower heated dies having corresponding male and female surfaces. During the forming process, pleats may be formed at the score lines.

The lid insert 16 may further include printing or other graphics on an exterior surface of the cover portion 22. One or more of the inside and outside surfaces of the lid insert 16 may be coated with a polymeric coating, a polymeric film or another material or liner suitable for impeding liquids or moisture from penetrating therethrough.

The container base 14, to which the lid 12 may be releasably attached, may take any suitable shape and may be in the form of a bowl, carton, box, tray, cup or other receptacle. Like the lid insert 16, the container base 14 can be constructed of any suitable material, including but not limited to a cellulosic or fiber-containing material, a paper-based material, a plastic material, a metallic material or any other suitable material now known or hereafter developed. One or more of the inside and outside surfaces of the container base 14 may be coated with a polymeric coating, a polymeric film or another material or liner suitable for impeding liquids or moisture from penetrating therethrough. In one preferred embodiment, the container base 14 is constructed of a recyclable or compostable material, such as molded fiber or paperboard. The container base 14 may be produced in a process that results in a generally flat rim 20 or in a process that results in a variable, wavy or bowed rim 20.

As shown in FIG. 2, one embodiment of the container base 14 includes a generally flat and horizontal peripheral rim 20 extending radially and outwardly at least partially or fully therearound that corresponds generally to the rim 24 of the lid insert 16. When the lid insert 16 is attached to or is otherwise covering the container base 14, the rim 24 of the lid insert 16 at least partially mates with the rim 20 of the container base 14. The lid insert's rim 24 may include a circumscribing outer edge 38 that is generally identical or similar in size and/or shape to a circumscribing outer edge 40 of the container base's rim 20. Like the lid insert 16, the base 14 may take form in a variety of shapes, including round, square, oval, rectangular or other suitable shapes. In fact, in one optional embodiment, the lid insert 16 is generally identical to the container base 14. In other words, the lid insert 16 may simply be an inverted or overturned container base 14, both of which may be constructed of a pressed paperboard material or a molded fiber material, for example. In such an embodiment, the lid insert 16 may be a mirror image of, and interchangeable with, the container base 14.

Turning attention now to the ring 18, it will be understood that the ring 18 may be constructed of a recyclable material, such as a plastic material, polymeric material, molded fiber material, metallic material or other suitable material now known or hereafter developed. The ring 18 may be formed in an injection molding process or a thermoforming process. The ring 18 may circumscribe all or a portion of the lid insert's rim 24.

A first embodiment of the ring 18 is illustrated in FIG. 2. In that embodiment, the ring 18 includes a generally horizontal flange 26 and a downwardly extending skirt 28. As shown, the ring 18 can include upper and lower inwardly extending locking projections or undercuts 30, 32. The undercuts 30, 32 may be in the form of ribs, barbs, lugs or other projections. The undercuts 30, 32 may each be in the form of a single projection that extends substantially continuously around the entire interior periphery of the skirt 28 or may include a plurality of peripherally-spaced projections having gaps therebetween where no projection is present. As depicted, an upper channel 34 is formed between the top side of the upper undercut 30 and the bottom surface of the ring's flange 26. A lower channel 36 is formed between the top side of the lower undercut 32 and the bottom side of the upper undercut 30. As demonstrated in FIG. 2, the outside edge 38 of the lid insert's rim 24 snaps into the upper channel 34 and is retained in the upper channel 34 so as to releasably lock the ring 18 to the lid insert 16. Similarly, the outside edge 40 of the base's rim 20 snaps into the lower channel 36 and is retained in the lower channel 36 so as to releasably lock the ring 18 to the base 14. As such, the ring 18 releasably locks the lid insert 16 to the base 14. Put differently, the lid insert 16 and base 14 may be in snapping engagement with one another via the ring 18. When a consumer desires to gain access to the contents (e.g., food) within the base 14, the consumer may grasp a lower portion 42 of the ring's skirt 28 and simultaneously pull outwardly and upwardly in order to disengage the outer edge 40 of the base's rim 20 from the ring's lower channel 36. The outer edge 38 of the lid insert's rim 24 may also optionally be disengaged from the ring's upper channel 34 during this process or may otherwise remain engaged in the upper channel 34.

A second embodiment of the ring 18 is illustrated in FIG. 5. The second embodiment is similar in nature to the first embodiment (shown in FIG. 2), except for that the second embodiment includes only a single locking projection or undercut 44. The undercut 44 may be in the form of ribs, barbs, lugs or other projections. The undercut 44 may be in the form of a single projection that extends substantially continuously around the entire interior periphery of the skirt 28 or may include a plurality of peripherally-spaced projections having gaps therebetween where no projection is present. A single channel 46 is formed between the top side of the undercut 44 and a bottom surface of the ring's flange 26. As demonstrated in FIG. 5, the outer edge 38 of the lid insert's rim 24 and the outer edge 40 of the base's rim 20 may both be retained in the channel 46 so as to releasably lock the lid insert 16 to the base 14 via the ring 18. When a consumer desires to gain access to the contents (e.g., food) within the base 14, the consumer may grasp a lower portion 42 of the ring's skirt 28 and simultaneously pull outwardly and upwardly in order to disengage the outer edge 40 of the base's rim 20 from the ring's channel 46. The outer edge 38 of the lid insert's rim 24 may also optionally be disengaged from the ring's channel 46 during this process or may otherwise remain engaged in the channel 46.

FIGS. 6 and 7 demonstrate a third embodiment of the present invention. In that embodiment, the ring 18 has a stepped cross section. The ring 18 may include a generally horizontal and outwardly extending upper flange 48, a downwardly extending upper skirt 50, a generally horizontal and outwardly extending lower flange 52, and a downwardly extending lower skirt 54. In this embodiment, the periphery of the lid insert's rim 24 may be smaller than the periphery of the base's rim 20.

As depicted, the upper skirt 50 may include one or more inwardly extending locking projections or undercuts 56 and the lower skirt 54 may include one or more inwardly extending locking projections or undercuts 58. The undercuts 56, 58 may be in the form of ribs, barbs, lugs or other projections. The undercuts 56, 58 may each be in the form of a single projection that extends substantially continuously around the entire interior periphery of their respective skirts 50, 54 or may include a plurality of peripherally-spaced projections having gaps therebetween where no projection is present. In one embodiment, the undercuts 58 of the lower skirt 54 may be positioned at various heights. Likewise, while not shown, the undercuts 58 of the upper skirt 50 may also be position at various heights.

In the same general manner as the embodiments described above, a channel is formed between the top side of each undercut 56 and the bottom surface of the ring's upper flange 48, wherein the channel is suitable for receiving the outer edge 38 of the lid insert's rim 24 therein for releasably locking the ring 18 to the lid insert 16. Similarly, a plurality of channels are formed between the top side of undercuts 58 and the bottom side of other undercuts 58 and/or the bottom surface of the ring's lower flange 52, wherein such channels are suitable for receiving the outer edge 40 of the base's rim 20 therein for releasably locking the ring 18 to the base 14. As demonstrated best in FIG. 7, this embodiment is particularly beneficial in retaining the ring 18 to a wavy base rim 20. Specifically, as depicted best in FIG. 7, multiple channels are formed at various heights about the lower skirt 54, whether formed between the undercuts 58 and the bottom surface of the lower flange 52 or formed between two or more of the undercuts 58, thereby permitting the base rim 20 to be captured in a channel regardless of variations in its height due to its waviness.

It will be appreciated that the skirts 28, 50, 54 of the various ring 18 embodiments discussed above may be slightly outwardly flared in order to guide and center the ring 18 with respect to the lid insert 16 and base 14. Further, the undercuts 30, 32, 44, 56, 58 may be made in other various shapes and depths to adjust the ring's degree of hold, ease of insertion and ease of removal. The undercuts 30, 32, 44, 56, 58 can have ramped or chamfered bottoms sides in order to facilitate the ring's 18 attachment to the lid insert 16 and base 14.

In all of the above-referenced embodiments, the plastic ring 18 is such that it can be attached to the lid insert 16 during use (see FIG. 3) and then easily and cleanly separated from the lid insert 16 by a consumer after use (see FIG. 4), so that a paper-based lid insert 16 and plastic ring 18 can be separately recycled or composted separately upon disposal.

As described above, the undercuts 30, 44, 56 are designed to bite and hold the lid insert's rim 24 strongly enough that the ring 18 will stay in position through the consumer's end use. However, since the ring 18 is preferably not glued or melted to the lid insert 16, the consumer can very easily remove or punch the lid insert 16 from the ring 18, such that the two components are separated for disposal. The lid insert 16 and the base 14 may be placed in one recycle bin, while the plastic ring 18 may be placed in a separate recycle bin. Alternatively, each of the three components may be placed in their own dedicated recycle bins so that paperboard, molded fiber and plastic materials are all separate from one another.

Turning now to the method of manufacture, in one embodiment, the lid insert 16 is formed in a molding or press process and then placed into an injection molding machine. The plastic ring 18 may be formed around the lid insert's rim 24 and particularly around its outer edge 38 to form the lid 12. When formed, the undercuts 30, 44, 56 of the ring 18 entrap the rim's outer edge 38.

In another embodiment, the lid insert 16 and ring 18 are formed in separate processes. For example, the lid insert 16 may be formed in a fiber molding process or a paperboard pressing process, whereas the ring 18 may be formed in a thermoforming process or an injection molding process and then combined with the lid insert 16 by an automated machine to form the lid 12. The thermoforming process may result in a cost savings over the injection molding process. Once complete, the lids 12 may be kept separate from the bases 14 until a product (e.g., food) is placed in the bases 14. At that time, the lids 12 may be snappingly engaged with the bases 14 to cover and contain the contents within the bases 14.

From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims. Since many possible embodiments of the invention may be made without departing from the scope thereof, it is also to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative and not limiting.

The constructions described above and illustrated in the drawings are presented by way of example only and are not intended to limit the concepts and principles of the present invention. Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms “having” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required”. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. 

What is claimed is:
 1. A container lid adapted to interlock with a container base having a peripheral rim, said lid comprising: a lid insert including a central cover portion and a generally flat and horizontal peripheral rim extending outwardly around at least part of said cover portion; a ring circumscribing at least part of said lid insert rim, said ring including a horizontal flange and a skirt depending downwardly therefrom; and a first locking projection extending inwardly from said skirt.
 2. The lid of claim 1, wherein said cover portion has an upwardly projecting central section.
 3. The lid of claim 2, wherein said cover portion is generally dome-shaped.
 4. The lid of claim 1, wherein said lid insert rim is releasably retained between said first locking projection and said flange.
 5. The lid of claim 1, wherein said ring is configured to be separated from said lid insert upon disposal of said lid.
 6. The lid of claim 1 further comprising a channel defined between said first locking projection and a bottom surface of said flange.
 7. The lid of claim 6, wherein said channel is sized and shaped to receive an outer edge of said lid insert rim.
 8. The lid of claim 6, wherein said channel is sized and shaped to receive both an outer edge of said lid insert rim and an outer edge of said base rim.
 9. The lid of claim 1 further comprising a second locking projection extending inwardly from said skirt, said second locking projection being located beneath said first locking projection.
 10. The lid of claim 1 further comprising a first channel defined between said first locking projection and a bottom surface of said flange, and a second channel defined between a second locking projection and said first locking projection.
 11. The lid of claim 10, wherein said first channel is sized and shaped to receive an outer edge of said lid insert rim and said second channel is sized and shaped to receive an outer edge of said base rim.
 12. The lid of claim 1, wherein said lid insert is constructed of a paper-based material and said ring is constructed of a plastic material.
 13. The lid of claim 1, wherein said ring is constructed of plastic and is injected molded onto said lid insert rim.
 14. The lid of claim 1, wherein said ring is thermoformed and then combined with said lid insert rim.
 15. A container lid adapted to interlock with a container base having a peripheral rim, said lid comprising: a lid insert including a central cover portion and a generally flat and horizontal peripheral lid rim extending around at least part of said cover portion; a ring circumscribing at least part of said lid insert rim, said ring including: a generally horizontal and outwardly extending upper flange; an upper skirt extending downwardly from said upper flange; a generally horizontal lower flange extending outwardly from said upper skirt; a lower skirt extending downwardly from said lower flange; a first locking projection extending inwardly from said upper skirt; and one or more second locking projections extending inwardly from said lower skirt.
 16. The lid of claim 15 further comprising a first channel defined between said first locking projection and a bottom surface of said upper flange.
 17. The lid of claim 16 further comprising a second channel defined between at least one of said second locking projections and a bottom surface of said lower flange.
 18. The lid of claim 17 further comprising a third channel defined between two said second locking projections.
 19. A method of manufacturing a lid adapted to interlock with a container base having a peripheral rim, said method comprising the steps of: forming a paper-based material into a lid insert having a peripheral rim; and forming an injection molded plastic ring around at least a portion of said lid insert rim, wherein said plastic ring includes a horizontal flange, a skirt depending downwardly from the horizontal flange and a locking projection extending inwardly from said skirt.
 20. A method of manufacturing a lid adapted to interlock with a container base having a peripheral rim, said method comprising the steps of: forming a paper-based material into a lid insert having a peripheral rim; and thermoforming a molded plastic ring that includes a horizontal flange, a skirt depending downwardly from the horizontal flange and a locking projection extending inwardly from said skirt; and combining said plastic ring and said lid insert. 